The GEOF-NTIS geoid based on Least Squares modification of Stokes integral with additive corrections for the Colorado Experiment: ColLSMSA-GEOF2019

Cite as:

Varga, Matej; Pitoňák, Martin; Novák, Pavel; Bašić, Tomislav (2019): The GEOF-NTIS geoid based on Least Squares modification of Stokes integral with additive corrections for the Colorado Experiment: ColLSMSA-GEOF2019. V. 1.0. GFZ Data Services. https://doi.org/10.5880/isg.2019.006

Status

I N R E V I E W : Varga, Matej; Pitoňák, Martin; Novák, Pavel; Bašić, Tomislav (2019): The GEOF-NTIS geoid based on Least Squares modification of Stokes integral with additive corrections for the Colorado Experiment: ColLSMSA-GEOF2019. V. 1.0. GFZ Data Services. https://doi.org/10.5880/isg.2019.006

Abstract

The ColLSMSA-GEOF2019 gravimetric geoid model has been computed by the Faculty of Geodesy, University of Zagreb (GEOF) in cooperation with the New technologies for the Information Society, University of West Bohemia (NTIS). It has been worked out in the frame of the International Association of Geodesy Joint Working Group 2.2.2 "The 1 cm geoid experiment" and the so called "Colorado experiment". The area covered by the model is 251°E ≤ longitude ≤ 257°E, 36°N ≤ latitude ≤ 39°N with a grid spacing of 1' in both latitude and in longitude.

The geoid is computed using a two-step procedure. First, the terrestrial and airborne gravity data are gridded by Least Squares Collocation (LSC) with a planar logarithmic covariance model in the framework of a remove-compute-restore procedure. Long wavelengths are modelled by XGM2016 up to degree and order 500, while short wavelengths are taken from the topographic gravity effect. In the second step, the resulting 1'x1' grid of Molodensky-type free-air gravity anomalies is used to compute geoidal heights by using Least Squares Modification of Stokes’ formula with Additive corrections (LSMSA). In particular, the geoidal heights are obtained by using a biased modification of the Stokes kernel (0.5° spherical cap size integration) and then by adding four corrections, namely topographic, downward continuation, atmospheric and ellipsoidal corrections. The accuracy of the geoid model, when compared against GSVS17 GPS/leveling, is equal to 3.9 cm.

The geoid model is provided in ISG format 2.0 (ISG Format Specifications), while the file in its original data format is available at the model ISG webpage.

Additional Information

The International Service for the Geoid (ISG) was founded in 1992 (as International Geoid Service - IGeS) and it is now an official service of the International Association of Geodesy (IAG), under the umbrella of the International Gravity Field Service (IGFS). The main activities of ISG consist in collecting, analysing and redistributing local and regional geoid models, as well as organizing international schools on the geoid determination (Reguzzoni et al., 2021).

Authors

Varga, Matej;Institute of Geodesy and Photogrammetry, ETH Zürich, Switzerland
Pitoňák, Martin;Faculty of Applied Sciences, University of West Bohemia, Plzeň, Czech Republic
Novák, Pavel;Faculty of Applied Sciences, University of West Bohemia, Plzeň, Czech Republic
Bašić, Tomislav;Faculty of Geodesy, University of Zagreb, Republic of Croatia